Question: Simplify to lowest terms. $\dfrac{15}{25}$
What is the greatest common factor (GCD) of 15 and 25? $15 = 3\cdot5$ $25 = 5\cdot5$ $\mbox{GCD}(15, 25) = 5$ $\dfrac{15}{25} = \dfrac{3 \cdot 5}{ 5\cdot 5}$ $\hphantom{\dfrac{15}{25}} = \dfrac{3}{5} \cdot \dfrac{5}{5}$ $\hphantom{\dfrac{15}{25}} = \dfrac{3}{5} \cdot 1$ $\hphantom{\dfrac{15}{25}} = \dfrac{3}{5}$